I reset the MFA on position 2 when I bought the car just over 1000 miles ago, (2-3 wks ago), by accident, pushing and poking things, but since then, and thrashing it occasionally, an average MPG of 37.
Did get it up to 50.1 doing about 45mph on a slowish drive to work (10 miles), but on an average dual carriageway trip about 34-37 MPG.
Interestingly, (he says!) doing 70MPH or 90MPH produces the same MPG 34-37 depending on the length of the drive.
Very interested in the whole drilling the holes idea, as mine is orignal throughout, and is typically sluggish, very deep accelerator pedal, feels like a two different engines almost. There is also a semi disturbubing, although probably normal dip/near stall in the revs if you tap/rev quickly up to about 2,500RPM before it settles again around (according to the MFA) 780/840 RPM. Would be interested to see other peoples figures on the MFA's to compare. I also have, although I thought it is an exhaust problem, a blow back, popping type noise occasionally when decelerating from high revs. Replaced the two middle parts of the exhaust, but not sure what causes it. Wrong mixture air/fuel?
If I wasn't desperate for a beer and running late I'd post them here now, but will do later.